diff --git a/src/addons/attach/attach.ts b/src/addons/attach/attach.ts
index 98a0bfaa1..f121e2e2d 100644
--- a/src/addons/attach/attach.ts
+++ b/src/addons/attach/attach.ts
@@ -53,7 +53,7 @@ export function attach(term: Terminal, socket: WebSocket, bidirectional: boolean
         const fileReader = new FileReader();
 
         fileReader.addEventListener('load', () => {
-          str = myTextDecoder.decode(this.result);
+          str = myTextDecoder.decode(fileReader.result);
           displayData(str);
         });
         fileReader.readAsArrayBuffer(ev.data);